It is neighbours at war, but this time the controversial extension is no normal conservatory, but a glazed hall big enough for a symphony orchestra.

On one side is the director of the National Theatre, Sir Nicholas Hytner, who has launched a stinging attack on the £120m redevelopment plans proposed by the next-door Southbank Centre, championed by its artistic director, Jude Kelly.

Hytner says the operators of the Royal Festival Hall and Hayward Gallery are threatening to cast his theatres into shadow, wrecking cherished river views and, perhaps most tartly, allowing commercial ambitions to trump respect for cultural heritage.

Hytner poured his concerns into a simmering 2,683-word formal objection that complains that the scheme will strike at the founding values of the National Theatre and will drive an unneighbourly wedge through the heart of Europe's largest cluster of arts venues.

The complaint was filed this week with the London Borough of Lambeth, which will decide on the plans this autumn. It claims "irreparable harm" will be done to the setting of the National Theatre's grade II*-listed buildings designed by Sir Denys Lasdun, and warns that "a signature night-time view of London" across the Thames is under threat. Hytner said the National has watched with growing concern at the plans, which are crowned by an "overscale and dominant" glass box rehearsal room with space for a full orchestra and choir. A new building that Hytner appears to consider the arts centre equivalent of a leylandii hedge will block out light and spoil vistas, he said.

The Southbank's chief executive, Alan Bishop, described the National's submission as having "a rather robust tone but that is Nick Hytner's normal tone" and pointed out that the National director had been invited to several consultation meetings but did not attend. He also said Hytner did not raise the issues with him before filing the complaint, although the National said two of its board members did. The Southbank Centre responded in a polite but defiant manner, directly challenging several of his neighbour's assertions and pledging to press on with a scheme that he sees as vital for the arts complex's continued success.

"We have very friendly relations with our neighbours next door so we were sad they are so concerned," Bishop said. "We are working on this very carefully and we know we can't make everybody happy but we have 27 million people pass through the site [every year] and we have to try to balance their needs against each other and those of our neighbours. We go on listening, but we go on making the case for what we proposed in the first place."

Hytner's attack is the latest setback for the Southbank Centre's ambitious plans to reconfigure a tangled cluster of brutalist 1960s concrete venues that includes the Hayward Gallery, Purcell Room and Queen Elizabeth Hall. The arts centre has long complained that the facilities are difficult to operate and increasingly costly to maintain, and that it needs to introduce more space for restaurants and cafes demanded by arts audiences as well as other money-making ventures. Objections have been plentiful ranging from English Heritage to the community of skateboarders who for decades have been drawn to the complex's smooth concrete undercrofts. Several attempts to resolve the site's problems have failed to come to fruition, including masterplans by Sir Terry Farrell, Lord Richard Rogers and the late Rick Mather who drew up the last scheme in 2000.

Hytner said it was right for the SBC to redevelop its site but the latest plans, produced this time by Bath-based architects Feilden Clegg Bradley, block views from the theatres' terraces and cast shade over public spaces that are currently bathed in afternoon and evening sunlight. A new building in line with Waterloo bridge and topped with a restaurant and roof garden, will drive a physical wedge between the Southbank Centre and the National Theatre, which will damage the public's perception of a unified arts quarter, he argues, even though it is operated by three organisations (NT, SBC and the British Film Institute). He said the so-called liner building has "a wall effect" presenting theatregoers with a view of its backside, structural beams and supports. The Southbank Centre insists it will improve the National's view and will be a "vibrant and welcoming face".

Hytner said the building's scale was "dictated not just by the cultural value but also the commercial ... so in fact the volume of the building that occludes the view of the National Theatre is largely dictated by the revenue it generates".

Bishop again denied the claim, insisting the building has a largely educational purpose and he said creating more commercial space "was the model we all have to embrace and the National Theatre knows that". Only £20m of the £120m required to build the scheme is coming from the public purse, and the largest contribution will be from bank loans underwritten by future commercial revenues.

Appropriately for an artistic dust-up, Hytner even reached for a literary reference to conclude his objection. He quoted the Edwardian actor-director-author Harley Granville-Barker, who floated plans for the National Theatre in 1907: "The National Theatre must … impose itself on public notice, not by posters and column advertisements in the newspapers but by the very fact of its ample, dignified and liberal existence."

"It has been, since 1976," Hytner added, "and it must remain so".

While the Southbank Centre's 1960s buildings have been recommended for listing on several occasions, they have never received protection from the government, unlike the grade II*-listed National Theatre and the grade I listed Royal Festival Hall, which is also part of the SBC.

Catherine Croft, chairwoman of the Twentieth Century Society, which has advised the National Theatre and the Southbank Centre on sensitive redevelopment, backed Hytner's views and complained that its advice had been ignored by the Southbank Centre. She said the proposal "overwhelms the existing buildings" and "turns its back" on the National.

"The South Bank is an amazing panorama, a vivid landscape of concrete volumes, and this scheme will obscure half of that," she said.

• This article was amended on 4 July 2013. An editing error led to an earlier version suggesting that the National Theatre's grade II*-listed buildings were designed by Sir Denys Lasdun in 1960; he was not appointed as the theatre's architect until 1963, and the building did not open until 1976.